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Quantitative analysis of the morphing wing mechanism of raptors: Analysis methods, folding motions, and bionic design of Falco Peregrinus

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Fundamental Research 2024年第2期4卷 344-352页

作者： Di Tang Xipeng Huang Jinqi Che Weijie Jin Yahui Cui yangjun chen Yuxiao Yuan Zhongyong Fan Weiwei Lu Siyu Wang Yin Yang Dawei Liu College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China Affiliated HangZhou XiXi hospital Zhejiang University School of MedicineHangzhou 310023China Zhejiang Museum of Natural History Hangzhou 310014China High Speed Aerodynamic Institute China Aerodynamics Research and Development CenterMianyang 621000China

Raptors can change the shape and area of their wings to an exceptional degree in a fast and efficient manner,surpassing other birds,insects,or bats.Some researchers have focused on the functional properties of muscle skeletons,mechanics,and flapping robot design.However,the wing motion of the birds of prey has not been measured quantitatively,and synthetic bionic wings with morphing abilities similar to raptors are far from reality.Therefore,in the current study,a 3D suspension system for holding bird carcasses was designed and fabricated to fasten the wings of Falco Peregrinus with a series of morphing postures.Subsequently,the wing skeleton of the falcon was scanned during extending motions using the computed tomography(CT)approach to obtain three consecutive poses.Subsequently,the skeleton was reconstructed to identify the contribution of the forelimb bones to the extending/folding motions.Inspired by these findings,we propose a simple mechanical model with four bones to form a wing-morphing mechanism using the proposed pose optimisation method.Finally,a bionic wing mechanism was implemented to imitate the motion of the falcon wing—divided into inner and outer wings with folding and twisting motions.The results show that the proposed four-bar mechanism can track bone motion paths with high fidelity.

关键词： Falco Peregrinus Raptor Suspension system CT scan Bionic wings Four-bar mechanism

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Responses of the field-aligned currents in the plasma sheet boundary layer to a geomagnetic storm

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Earth and Planetary Physics 2023年第5期7卷 558-564页

作者： YuanQiang chen MingYu Wu yangjun chen SuDong Xiao GuoQiang Wang TieLong Zhang Shenzhen Key Laboratory of Numerical Prediction for Space Storm Harbin Institute of TechnologyShenzhen 518055China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Chinese Academy of Sciences Center for Excellence in Comparative PlanetologyHefei 230026China Space Research Institute Austrian Academy of SciencesGraz 8042Austria

Geomagnetic storms can result in large magnetic field disturbances and intense currents in the magnetosphere and even on the ground.As an important medium of momentum and energy transport among the solar wind,magnetosphere,and ionosphere,field-aligned currents(FACs)can also be strengthened in storm times.This study shows the responses of FACs in the plasma sheet boundary layer(PSBL)observed by the Magnetospheric Multiscale(MMS)spacecraft in different phases of a large storm that lasted from May 27,2017,to May 29,2017.Most of the FACs were carried by electrons,and several FACs in the storm time also contained sufficient ion FACs.The FAC magnitudes were larger in the storm than in the quiet period,and those in the main phase were the strongest.In this case,the direction of the FACs in the main phase showed no preference for tailward or earthward,whereas the direction of the FACs in the recovery phase was mostly tailward.The results suggest that the FACs in the PSBL are closely related to the storm and could be driven by activities in the tail region,where the energy transported from the solar wind to the magnetosphere is stored and released as the storm is evolving.Thus,the FACs are an important medium of energy transport between the tail and the ionosphere,and the PSBL is a significant magnetosphere–ionosphere coupling region in the nightside.

关键词： field-aligned currents plasma sheet boundary layer geomagnetic storm

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Sources and transformations of nitrite in the Amundsen Sea in summer 2019 and 2020 as revealed by nitrogen and oxygen isotopes

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Acta Oceanologica Sinica 2023年第4期42卷 16-24页

作者： yangjun chen Jinxu chen Yi Wang You Jiang Minfang Zheng Yusheng Qiu Min chen College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China School of Marine Science and Fisheries Jiangsu Ocean UniversityLianyungang 222005China

In this study,the nitrogen and oxygen isotope compositions of nitrite in the upper 150 m water column of the Amundsen Sea in the summer of 2019 and 2020 were measured to reveal the distribution and transformation of nitrite in the euphotic zone of the Southern Ocean.We found that primary nitrite maxima(PNMs)are widely present in the Amundsen Sea,where the depth of occurrence deepens from east to west and nitrite concentrations increases.Evidence from dual isotopes suggests that the formation of PNMs in all regions of the Amundsen Sea is dominated by ammonia oxidation.More importantly,the nitrogen and oxygen isotope compositions of nitrite in the Amundsen Sea mixed layer are abnormal,and their depth profiles are mirror symmetrical.Isotopic anomalies exhibit spatial variations,with central surface water having the lowest nitrogen isotope composition(−89.9‰±0.2‰)and western surface water having the highest oxygen isotope composition(63.3‰±0.3‰).Isotopic exchange reaction between nitrate and nitrite is responsible for these isotope anomalies,as both nitrogen and oxygen isotopes have large isotopic fractionation and opposite enrichment effects.This proves that isotopic exchange reaction operates extensively in different regions of the Amundsen Sea.Our study highlights the unique role of dual isotopes of nitrite in deepening the understanding of nitrogen cycle.Further studies on ammonia oxidation and isotopic exchange between nitrate and nitrite are warranted in the future to understand their roles in the nitrogen cycle in the Southern Ocean.

关键词： nitrogen isotope oxygen isotope nitrite Amundsen Sea

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Biomimetic hybrid hydrogel for hemostasis,adhesion prevention and promoting regeneration after partial liver resection

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Bioactive Materials 2022年第5期7卷 41-51页

作者： Zuhong Li Yalei Zhao Xiaoxi Ouyang Ya Yang yangjun chen Qixia Luo Yanhong Zhang Danhua Zhu Xiaopeng Yu Lanjuan Li State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou310003China School of Ophthalmology&Optometry Eye HospitalWenzhou Medical UniversityWenzhou325027China

Partial liver resection is an established treatment for hepatic disorders.However,surgical bleeding,intra-abdominal adhesion and rapid liver regeneration are still major challenges after partial liver resection,associated with morbidity and mortality.Herein,a biomimetic hybrid hydrogel,composed of oxidized hyaluronic acid,glycol chitosan and MenSCs-derived conditioned medium(CM),is presented to address these issues.The hybrid hydrogel is formed through reversible Schiff base,and possesses injectability and self-healing capability.Moreover,hybrid hydrogel exhibits the capabilities of hemostasis,anti-infection,tissue adhesion and controllable release of cargoes.Based on in vivo studies of the multifunctional hybrid hydrogel,it is demonstrated that acute bleeding in partial liver resection can be ceased immediately by virtue of the hemostasis features of hybrid hydrogel.Also,a significant reduction of intra-abdominal adhesion is confirmed in hybrid hydrogel-treated resection surface.Furthermore,upon the treatment of hybrid hydrogel,hepatic cell proliferation and tissue regeneration can be significantly improved due to the controllably released cytokines from MenSCs-derived CM,exerting the effects of mitogenesis and anti-inflammation in vivo.Thus,the biomimetic hybrid hydrogel can be a promising candidate with great potential for application in partial liver resection.

关键词： Hybrid hydrogel Partial liver resection Hemostasis Adhesion prevention Liver regeneration

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微塑料对沉积物及其上覆水体氮循环的影响研究

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海洋环境科学 2024年第2期43卷 262-272页

作者：陈雪婷张兴洲刘诗伟陈阳军冯志华江苏海洋大学江苏省海洋生物资源与环境重点实验室江苏连云港222005 江苏海洋大学江苏省海洋生物产业技术联合创新中心江苏连云港222005 江苏海洋大学自然资源部滨海盐沼湿地生态与资源重点实验室江苏连云港222005

海洋氮循环是海洋元素循环的重要组成部分,由不同材质类型的微生物所驱动,对评估海洋生态系统的结构和功能具有重要的意义。鉴于微塑料对海洋生态环境的胁迫,有必要厘清微塑料的存在对氮转化过程的影响,以提升对当代及未来海洋氮循环的... 详细信息

海洋氮循环是海洋元素循环的重要组成部分,由不同材质类型的微生物所驱动,对评估海洋生态系统的结构和功能具有重要的意义。鉴于微塑料对海洋生态环境的胁迫,有必要厘清微塑料的存在对氮转化过程的影响,以提升对当代及未来海洋氮循环的理解。据此,本研究设置不同浓度(0.5%和0.05%)、不同粒径(500目、150目和16目)和不同材质类型(PA、PE、PVC、PP、PS)的微塑料暴露实验,评估微塑料的存在是否对海洋沉积物及周边水体氮转化过程存在影响。结果表明,微塑料的存在会改变氧化还原环境,继而对微生物所驱动的氮循环过程产生影响。另外,研究发现,微塑料的材质类型、浓度和粒径分别会对氮循环过程产生不同的影响,意味着微塑料的不同性质会改变海洋沉积物及周边水体的氮循环过程。微塑料会通过影响沉积物中微生物的组成和活性进而影响上覆水中氮素分布,对水体氮循环构成挑战。后续的研究需要深入探究微塑料影响下上覆水中氮循环的同位素动力学,以提升对氮循环的理解。

关键词：微塑料氮循环沉积物亚硝酸盐硝酸盐

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抗结核药物联合胸腺五肽治疗复治涂阳肺结核的效果分析

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中国社区医师 2024年第9期40卷 56-58页

作者：杨艳陆霓虹孙娅萍陈杨君昆明市第三人民医院云南昆明650041

目的:分析抗结核药物联合胸腺五肽治疗复治涂阳肺结核的效果。方法:选取2021年2月—2022年2月昆明市第三人民医院收治的84例复治涂阳肺结核患者作为研究对象,随机分为对照组与试验组,各42例。对照组接受抗结核药物治疗,采用3HRZE/6HRE... 详细信息

目的:分析抗结核药物联合胸腺五肽治疗复治涂阳肺结核的效果。方法:选取2021年2月—2022年2月昆明市第三人民医院收治的84例复治涂阳肺结核患者作为研究对象,随机分为对照组与试验组,各42例。对照组接受抗结核药物治疗,采用3HRZE/6HRE给药方案,试验组在对照组基础上应用胸腺五肽治疗。比较两组治疗效果。结果:试验组痰菌转阴率、病灶吸收率、空洞闭合率均高于对照组,差异有统计学意义(P<0.05)。治疗后,两组CD8+水平低于治疗前,且试验组低于对照组,两组CD4+、CD4+/CD8+水平高于治疗前,且试验组高于对照组,差异有统计学意义(P<0.05)。两组不良反应总发生率比较,差异无统计学意义(P=0.101)。结论:抗结核药物联合胸腺五肽治疗复治涂阳肺结核的效果较好,能够增强机体免疫功能,且安全性好,值得应用并予以推广。

关键词：抗结核药物胸腺五肽复治涂阳肺结核免疫功能

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欧前胡素调节ERK/MAPK信号通路对肺结核大鼠炎症反应的影响

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西部医学 2024年第1期36卷 24-28,35页

作者：陈杨君陆霓虹刘洪璐杨艳刘梅艳昆明市第三人民医院呼吸与危重症医学科云南昆明650041

目的探讨欧前胡素(Imp)调节细胞外调节蛋白激酶(ERK)/有丝分裂原激活蛋白激酶(MAPK)信号通路对肺结核大鼠炎症反应的影响。方法 64只大鼠随机分为对照组12只及造模组52只,造模组大鼠通过尾部注射结核杆菌方法建立肺结核大鼠模型,之后... 详细信息

目的探讨欧前胡素(Imp)调节细胞外调节蛋白激酶(ERK)/有丝分裂原激活蛋白激酶(MAPK)信号通路对肺结核大鼠炎症反应的影响。方法 64只大鼠随机分为对照组12只及造模组52只,造模组大鼠通过尾部注射结核杆菌方法建立肺结核大鼠模型,之后随机分为模型组、Imp低(Imp-L,25 mg/kg)、中(Imp-M,50 mg/kg)、高剂量(Imp-H,100 mg/kg)组、Imp-H+ERK特异性激活剂(EGF,100 mg/kg Imp+25 mg/kg EGF)组。干预结束后,主动脉采血,ELISA检测各组大鼠血清中白细胞介素-6(IL-6)、γ干扰素(IFN-γ)、环氧化酶-2(COX-2)水平;分离肺组织,HE、Tunel分别检测大鼠肺组织病理学变化及细胞凋亡情况;统计肺组织中结核杆菌菌落数;Western blot检测p-ERK1/2/ERK1/2、p38 MAPK表达水平。结果与对照组相比,模型组肺组织严重病变,IL-6、IFN-γ、COX-2、细胞凋亡率、结核杆菌菌落数、p-ERK1/2/ERK1/2、p38 MAPK表达均显著增加(P<0.05);与模型组相比,Imp-L组、Imp-M组、Imp-H组病理损伤得到缓解,IL-6、IFN-γ、COX-2、细胞凋亡率、结核杆菌菌落数、p-ERK1/2/ERK1/2、p38 MAPK表达显著降低,以Imp-H组变化最为显著(P<0.05);与Imp-H组相比,Imp-H+EGF组病理损伤进一步加重,IL-6、IFN-γ、COX-2、细胞凋亡率、结核杆菌菌落数、p-ERK1/2/ERK1/2、p38 MAPK表达显著增加(P<0.05)。结论 Imp可降低肺结核炎症反应,与抑制ERK/MAPK信号通路的激活有关。

关键词：肺结核欧前胡素 ERK/MAPK信号通路炎症反应

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七种不同基质金属蛋白酶在抗结核药物性肝损伤小鼠模型中的表达与临床价值

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中国医药导报 2024年第4期21卷 6-10页

作者：陆霓虹杜映荣刘洪璐陈杨君杨永锐昆明市第三人民医院云南省传染性疾病临床医学中心云南昆明650041

目的探讨7种不同基质金属蛋白酶(MMP)在抗结核药物性肝损伤小鼠模型中的表达与临床价值。方法选取120只雄性昆明小鼠,SPF级,6周龄,体重18~24 g,随机区组法分为6组,每组20只。一组设为对照组,五组感染结核分枝杆菌后分别灌胃异烟肼(INH)... 详细信息

目的探讨7种不同基质金属蛋白酶(MMP)在抗结核药物性肝损伤小鼠模型中的表达与临床价值。方法选取120只雄性昆明小鼠,SPF级,6周龄,体重18~24 g,随机区组法分为6组,每组20只。一组设为对照组,五组感染结核分枝杆菌后分别灌胃异烟肼(INH)45 mg/(kg·d)(INH组)、利福平(RIF)90 mg/(kg·d)(RIF组)、乙胺丁醇(EB)135 mg/(kg·d)(EB组)、吡嗪酰胺(PZA)180 mg/(kg·d)(PZA组)、四联抗结核药(INH+RIF+EB+PZA)剂量同上(四联药组),建立抗结核药物性肝损伤小鼠模型。通过酶联免疫吸附试验法检测药物灌胃后12 h及1、2、3周小鼠模型血清中MMP-1、2、3、7、9、13、14的表达水平,分析其与肝脏指数变化的相关性,探讨不同MMP在抗结核药物性肝损伤中的作用。结果给药12 h,与对照组比较,RIF组MMP-7表达上调,差异有统计学意义(P0.05)。连续灌胃1周,与对照组比较,INH组、RIF组和四联药组小鼠MMP-2和MMP-7表达上调,肝脏指数升高,差异有统计学意义(P0.05)。连续灌胃药物2、3周后,与对照组比较,RIF组、INH组、四联药组小鼠血清MMP-2、7、9表达上调,肝脏指数升高,差异有统计学意义(P0.05)。INH组MMP-2、7、9与肝脏指数无相关性(P>0.05),四联药组MMP-2、7、9与肝脏指数无相关性(P>0.05)。RIF组MMP-7与肝脏指数呈正相关(r=0.981,P<0.05)。结论抗结核药物性肝损伤小鼠血清MMP-2、MMP-7和MMP-9明显升高,提示MMP-2、MMP-7和MMP-9介导的炎症反应与抗结核药物性肝损伤密切相关,其中MMP-7可用于预判抗结核药物性肝损伤严重程度。

关键词：基质金属蛋白酶2 基质金属蛋白酶7 基质金属蛋白酶9 抗结核药物性肝损伤小鼠模型

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Flow Loss Mechanism in a Supercritical Carbon Dioxide Centrifugal Compressor at Low Flow Rate Conditions

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Journal of Thermal Science 2024年第1期33卷 114-125页

作者： YANG Zimu JIANG Hongsheng ZHUGE Weilin CAI Ruikai YANG Mingyang chen Haoxiang QIAN Yuping ZHANG yangjun State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

With the advantages of high efficiency and compact structure,supercritical carbon dioxide(sC02)Brayton cycles have bright prospects for development in energy conversion field.As one of the core components of the power cycle,the centrifugal compressor tends to operate near the critical point(304.13 K,7.3773 MPa).Normally,the compressor efficiency increases as the inlet temperature decreases.When the inlet temperature is close to the critical point,the density increases sharply as the temperature decreases,which results in quickly decreasing of volume flow rate and efficiency reducing.The flow loss mechanism of the sCO_(2) compressor operating at low flow rate is studied in this paper.Computational fluid dynamics(CFD) simulations for sCO_(2)compressor were carried out at various inlet temperatures and various mass flow rates.When the sCO_(2)compressor operates at low volume flow rate,the flow loss is generated mainly on the suction side near the trailing edge of the blade.The flow loss is related to the counterclockwise vortexes generated on the suction side of the main blade.The vortexes are caused by the flow separation in the downstream region of the impeller passage,which is different from air compressors operating at low flow rates.The reason for this flow separation is that the effect of Coriolis force is especially severe for the sCO_(2) fluid,compared to the viscous force and inertial force.At lower flow rates,with the stronger effect of Coriolis force,the direction of relative flow velocity deviates from the direction of radius,resulting in its lower radial component.The lower radial relative flow velocity leads to severe flow separation on the suction side near the trailing edge of the main blade.

关键词： supercritical CO_(2) centrifugal compressor flow loss mechanism Coriolis force

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抗结核药物性肝损伤小鼠模型细胞角蛋白18与基质金属蛋白酶7的表达水平

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中国医药导报 2024年第12期21卷 1-5页

作者：陆霓虹刘洪璐陈杨君杨永锐孙娅萍杨艳杜映荣李红娟昆明市第三人民医院云南省传染性疾病临床医学中心云南昆明650041

目的分析抗结核药物性肝损伤(ATB-DILI)模型小鼠组织及血清中细胞角蛋白18(CK18)与基质细胞金属蛋白酶7(MMP-7)表达,探讨CK18与MMP-7在肝损伤发生中的临床价值。方法 6周龄SPF级雄性KM小鼠20只,体重18~24 g,按照随机区组法分为4组,每组... 详细信息

目的分析抗结核药物性肝损伤(ATB-DILI)模型小鼠组织及血清中细胞角蛋白18(CK18)与基质细胞金属蛋白酶7(MMP-7)表达,探讨CK18与MMP-7在肝损伤发生中的临床价值。方法 6周龄SPF级雄性KM小鼠20只,体重18~24 g,按照随机区组法分为4组,每组5只。选择3组进行卡介苗(BCG)滴鼻使小鼠感染结核分枝杆菌,其中两组分别灌胃异烟肼(INH)45 mg/(kg·d)、利福平(RIF)90 mg/(kg·d),持续3周,记为INH 3周组及RIF3周组,剩余一组为BCG感染对照组;未经任何处理的为空白对照组。通过PCR检测小鼠肺组织BCG含量,病理观察小鼠肝损伤证实动物模型建立成功。比较各组肝脏指数、病变范围;比较各组小鼠血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、碱性磷酸酶(ALP)、γ-谷氨酰转移酶(GGT)、总胆红素(TBil)、CK18、MMP-7表达情况;比较各组小鼠肝脏组织CK18、MMP-7蛋白表达情况。结果 BCG感染对照组与空白对照组小鼠ALT、AST、ALP、GGT、TBil表达比较,差异无统计学意义(P>0.05);INH 3周组和RIF 3周组小鼠ALT、AST、GGT、TBil表达高于BCG感染对照组(P0.05);INH 3周组、RIF 3周组小鼠肝脏组织CK18、MMP-7蛋白表达高于BCG感染对照组(P0.05);INH 3周组、RIF 3周组小鼠血清CK18、MMP-7表达高于BCG感染对照组(P0.05);INH 3周组、RIF 3周组小鼠肝脏指数、病变范围高于BCG感染对照组(P<0.05)。结论 CK18与MMP-7可能影响ATB-DILI,明确CK18与MMP-7表达水平,提前干预,可以降低ATB-DILI发生风险。

关键词：基质金属蛋白酶7 细胞角蛋白18 抗结核药物性肝损伤小鼠模型

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